This is where I'm currently migrating all old references for my Dead by Daylight tools. In the meantime, don't get lost in the fog...
Currently, these tools are being migrated:
The current player progression system rewards iridescent shards per level, not like the old one at the end of a match. In order to do that, you now earn XP per game instead of iridescent shards directly. Thanks to the work done by the Dead by Daylight wiki team, we've already got a conclusive list on how much XP you need per level to level up.
Hmm. Looks like I didn't insert the table here yet. Why don't you check here?
If you look at it, you can see that every level rewards a few shards. Wouldn't it be fun to know how many shards exactly? And how quickly you're earning them? That's what this calculation is about.
Okay, so let's look at it. The list references the XP required for the level up itself, not what you gain from this level. So level 2 means level 1 level up to 2 etc.
720 +900 +(6-4+1)*1200 +(14-7+1)*2100 +(24-15+1)*2700 +(34-25+1)*3300 +(49-25+1)*3750 +(100-50+1)*4200 = 389970
Why the +1, you may wonder. If you look at it closely, you can see that, for example, Level 4, 5 and 6 require 1200 XP. However, those are 3 levels, not 2 (as 6-4 would yield). So we need to adapt to this. This calculation yields a total of 389970 XP required for ranking up to the next devotion tier. But how many shards does ranking up a devotion tier yield? In order to do that, we'll run a similar calculation.
50 +65 +(6-4+1)*85 +(14-7+1)*150 +(24-15+1)*195 +(34-25+1)*235 +(49-35+1)*270 +(100-50+1)*300 = 25220
During one full devotion run, you're earning 25220 Iridescent Shards. That's a lot... but how much per experience point?
25220 / 389970 = 0.064671641408313
~0.065 Iridescent Shards per XP point isn't too bad at all. That's ~3.88 Shards per minute, or ~232.82 Shards per hour. Assuming a DLC character costs 9000 Shards, that means grinding one takes ~38.7 hours in-game. A fair amount which should be easily achievable for dedicated players.
It seems like Behavior has tweaked these values since my last calcuation a few years back. You might find outdated values on the Wiki. I'll try my best to keep them up to date here.